In the year 1756, he made a religious visit to several of the Society in Long Island. Here it was that the seed, now long fostered by the genial influences of Heaven, began to burst forth into fruit. Till this time he seems to have been a passive instrument, attending only to such circumstances as came in his way on this subject. But now he became an active one, looking out for circumstances for the exercise of his labours. "My mind," says he, "was deeply engaged in this visit, both in public and private; and at several places observing that members kept slaves, I found myself under a necessity, in a friendly way, to labour with them on that subject, expressing, as the way opened, the inconsistency of that practice with the purity of the Christian religion, and the ill effects of it as manifested amongst us."
In the year 1757, he felt his mind so deeply interested on the same subject, that he resolved to travel over Maryland, Virginia, and North Carolina, in order to try to convince persons, principally in his own Society, of the inconsistency of holding slaves. He joined his brother with him in this arduous service. Having passed the Susquehanna into Maryland, he began to experience great agitation of mind. "Soon after I entered this province," says he, "a deep and painful exercise came upon me, which I often had some feeling of since my mind was drawn towards these parts, and with which I had acquainted my brother, before we agreed to join as companions.
"As the people in this and the southern provinces live much on the labour of slaves, many of whom are used hardly, my concern was that I might attend with singleness of heart to the voice of the true Shepherd, and be so supported, as to remain unmoved at the faces of men."
It is impossible for me to follow him in detail, through this long and interesting journey, when I consider the bounds I have prescribed to myself in this work. I shall say therefore, what I purpose to offer generally and in a few words.
It appears that he conversed with persons occasionally, who were not of his own Society, with a view of answering their arguments, and of endeavouring to evince the wickedness and impolicy of slavery. In discoursing with these, however strenuous he might appear, he seems never to have departed from a calm, modest, and yet dignified and even friendly demeanour. At the public meetings for discipline, held by his own Society in these provinces, he endeavoured to display the same truths and in the same manner, but particularly to the elders of his own Society, exhorting them, as the most conspicuous rank, to be careful of their conduct, and to give a bright example in the liberation of their slaves. He visited also families for the same purpose: and he had the well-earned satisfaction of finding his admonitions kindly received by some, and of seeing a disposition in others to follow the advice he had given them.
In the year 1758, he attended the yearly meeting at Philadelphia, where he addressed his brethren on the propriety of dealing with such members, as should hereafter purchase slaves. On the discussion of this point he spoke a second time, and this to such effect that he had the satisfaction at this meeting to see minutes made more fully than any before, and a commitee appointed, for the advancement of the great object, to which he had now been instrumental in turning the attention of many, and to witness a considerable spreading of the cause. In the same year also, he joined himself with two others of the Society to visit such members of it, as possessed slaves in Chester county. In this journey he describes himself to have met with several, who were pleased with his visit but to have found difficulties with others, towards whom however he felt a sympathy and tenderness on account of their being entangled by the spirit of the world.
In the year 1759, he visited several of the Society who held slaves in Philadelphia. In about three months afterwards, he travelled there again, in company with John Churchman, to see others under similar circumstances. He then went to different places on the same errand. In this last journey he went alone. After this he joined himself to John Churchman again, but he confined his labours to his own province. Here he had the pleasure of finding that the work prospered. Soon after this he took Samuel Eastburne as a coadjutor, and pleaded the cause of the poor Africans with many of the Society in Bucks county, who held them in bondage there.
In the year 1760, he travelled, in company with his friend Samuel Eastburne, to Rhode Island, to promote the same object. This island had been long noted for its trade to Africa for slaves. He found at Newport, the great sea-port town belonging to it, that a number of them had been lately imported. He felt his mind deeply impressed on this account. He was almost overpowered in consequence of it, and became ill. He thought once of promoting a petition to the legislature, to discourage all such importations in future. He then thought of going and speaking to the House of Assembly, which was then sitting; but he was discouraged from both these proceedings. He held, however, a conference with many of his own Society in the meeting-house-chamber, where the subject of his visit was discussed on both sides, with a calm and peaceable spirit. Many of those present manifested the concern they felt at their former practices, and others a desire of taking suitable care of their slaves at their decease. From Newport he proceeded to Nantucket; but observing the members of the Society there to have few or no slaves, he exhorted them to persevere in abstaining from the use of them, and returned home.
In the year 1761, he visited several families in Pennsylvania, and, in about three months afterwards, others about Shrewsbury and Squan in New Jersey. On his return he added a second part to the treatise before published on the keeping of slaves, a care which had been growing upon him for some years.
In the year 1762, he printed, published, and distributed this treatise.